# CVE-2026-59276: Spring Security timing attack on security-sensitive string comparison

Source: https://junglewise.ai/threats/cve-2026-59276-spring-security-timing-attack-on-security-sensitive-string  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-27. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-59276 · Severity: medium · CVSS 5.9 · Published 2026-08-27

Spring Security uses standard string comparison instead of constant-time comparison for security-sensitive values, allowing attackers to determine correct values through timing analysis. This affects authentication and token validation components across multiple versions, potentially enabling attackers to forge or crack security credentials by observing response times.

Technologies: [VMware Spring Security](https://junglewise.ai/threats/technologies/spring-security). Vendors: [VMware](https://junglewise.ai/threats/vendors/vmware).

## Quick answers

**Is CVE-2026-59276 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-59276 being exploited in the wild.

**How severe is CVE-2026-59276?** Medium severity, with a CVSS score of 5.9, published 27 August 2026.

**Which products and versions are affected?** VMware Spring Security 5.7.0–5.8.27, 6.4.0–6.5.11, 7.0.0–7.1.0.

**Is there a fix for CVE-2026-59276?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-59276 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-59276?** Check whether you run VMware Spring Security at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

Multiple Spring Security components use String.equals() instead of a constant-time comparison function to verify security-sensitive values. The vulnerability allows attackers to exploit timing side-channels: String.equals() returns immediately upon finding the first mismatched character, making the comparison time proportional to the number of correct leading characters. This timing information can be used to systematically guess correct values (e.g., CSRF tokens, authentication strings) without triggering normal authentication failures. The issue affects Spring Security versions 5.7.0–5.8.27, 6.4.0–6.5.11, and 7.0.0–7.1.0.

## Affected products

- VMware Spring Security 5.7.0–5.8.27, 6.4.0–6.5.11, 7.0.0–7.1.0

## Timeline

- 2026-08-27: disclosed

## References

- [https://spring.io/security/cve-2026-59276](https://spring.io/security/cve-2026-59276)

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